Three-dimensional model reconstruction, motion simulation and biomechanical visualization of knee joints.

摘要

Virtual medical simulation is one of the major applications for computer graphics. This dissertation develops new methodologies to solve some key problems in constructing a virtual medical simulation system for the human knee joint.; First, I introduce a new 3D reconstruction technique that generate patient specific and highly detailed 3D knee model from medical images. The key steps of this technique are image pre-segmentation, correspondence establishments and reference model deformation. The 3D model is obtained by deforming a reference model to match the MRI dataset. This new approach is highly efficient and easy to control. The resulting model has good inherent connectivity and smoothness.; Second, I present a new algorithm for knee motion simulation. The knee motion is simulated by animating the 3D knee model based on the motion data collected from real patients. Collision detection techniques are used to adjust the knee rotation angles and find an optimal position. This motion simulation method presented in this dissertation is the first effort to visualize patient motion data on patient specific 3D model.; Third, I propose a new approach for visualizing biomechanical information on 3D knee model is proposed. The approach presented in this dissertation provides a new way for calculating and visualizing the knee contact area. A new real-time deformation technique is also proposed to simulate the deformation of menisci.; Finally, I propose a new approach for calculating and visualizing the contact forces between femur and tibia. The model significantly simplifies the classical biomechanical knee model by reducing the number of non-linear equations involved. Compared to the classical biomechanical analysis methods, this model is more efficient and better represents the real situation of patient knee joint. The result of the force analysis can be easily visualized by the use of a 3D model.; The work reported here is the first effort to integrate 3D reconstruction, motion simulation, and biomechanical visualization into one system.